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Adipose tissue lipolysis occurs during the development of heart failure as a consequence of chronic adrenergic stimulation. However, the impact of enhanced adipose triacylglycerol hydrolysis mediated by adipose triglyceride lipase (ATGL) on cardiac function is unclear. To investigate the role of adipose tissue lipolysis during heart failure, we generated mice with tissue-specific deletion of ATGL (atATGL-KO). atATGL-KO mice were subjected to transverse aortic constriction (TAC) to induce pressure-mediated cardiac failure. The cardiac mouse lipidome and the human plasma lipidome from healthy controls (n = 10) and patients with systolic heart failure (HFrEF, n = 13) were analyzed by MS-based shotgun lipidomics. TAC-induced increases in left ventricular mass (LVM) and diastolic LV inner diameter were significantly attenuated in atATGL-KO mice compared to wild type (wt) -mice. More importantly, atATGL-KO mice were protected against TAC-induced systolic LV failure. Perturbation of lipolysis in the adipose tissue of atATGL-KO mice resulted in the prevention of the major cardiac lipidome changes observed after TAC in wt-mice. Profound changes occurred in the lipid class of phosphatidylethanolamines (PE) in which multiple PE-species were markedly induced in failing wt-hearts, which was attenuated in atATGL-KO hearts. Moreover, selected heart failure-induced PE species in mouse hearts were also induced in plasma samples from patients with chronic heart failure. TAC-induced cardiac PE induction resulted in decreased PC/ PE-species ratios associated with increased apoptotic marker expression in failing wt-hearts, a process absent in atATGL-KO hearts. Perturbation of adipose tissue lipolysis by ATGL-deficiency ameliorated pressure-induced heart failure and the potentially deleterious cardiac lipidome changes that accompany this pathological process, namely the induction of specific PE species. Non-cardiac ATGL-mediated modulation of the cardiac lipidome may play an important role in the pathogenesis of chronic heart failure., Author summary Chronic heart failure (CHF) is still one of the leading causes of morbidity and mortality worldwide, and new therapeutic approaches are required. Here we show that perturbation of adipose tissue lipolysis by tissue-specific deletion of the lypolytic enzyme ATGL (adipose trigylceride lipase) protects against heart failure development. By using MS-based lipidomics we show that the lack of ATGL in adipose tissue protects the heart against deleterious cardiac lipidome changes such as increases of phosphatidylethanolamines. Changes of cardiac phosphatidylethanolamines may contribute to adipose ATGL-mediated heart failure pathophysiology by an impairment of cell membrane integrity. These data point towards a crucial function of ATGL in adipose tissue by regulating processes outside of the primary target tissue such as the heart. This is a new concept which may lead to alternative studies of gene function with a focus on non-target tissue and tissue/ organ interactions. Furthermore, therapeutic targeting of non-cardiac tissue may provide new opportunities for future heart failure therapy.

A generic approach to design optoelectronic devices using renewable biopolymers is demonstrated. As a proof of principle, a biopolymer/CuInS2 nanocomponent-based solar cell has been assembled by using a cellulose derivative with a reasonable life cycle performance, namely, trimethylsilyl cellulose (TMSC). The solar cells are manufactured using a mixture of copper and indium xanthates as precursors, which decompose and form CIS nanoparticles within the biopolymer matrix during a thermal treatment, which was investigated by in situ combined grazing incidence small and wide-angle X-ray scattering experiments. The growth of the nanoparticles is thereby controlled by the TMSC matrix. The nanocrystals exhibit an average diameter of approximately 4 nm. Using this composite, it was possible to fabricate solar cells, generating current in a wide range of the solar spectrum and exhibiting power conversion efficiencies of ca. 1%.

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In this study, the influence of device architecture (regular versus inverted) and different interlayers on performance and lifetime of polymer-nanocrystal hybrid solar cells is explored. The absorber layers of the investigated solar cells consist of the low band gap conjugated polymer poly[[9-(1-octylnonyl)-9H-carbazole-2,7-diyl]-2,5-thiophenediyl-2,1,3-benzothiadiazole-4,7-diyl-2,5-thiophenediyl] (PCDTBT) and copper indium sulfide (CIS) nanocrystals. These are prepared directly in the polymer matrix via an in situ approach using copper and indium xanthates, which are converted to CIS nanocrystals by mild thermal annealing. Different interlayers – poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) and inorganic metal oxides (V2O5, MoO3) – are used as hole extraction layers between absorber and anode. All three layers were successfully applied in solar cells in regular architecture. Using an inverted device design, a PEDOT:PSS interlayer and Ag electrodes, open circuit voltages of 550mV could be obtained, which are comparable to values obtained with solar cells having easily oxidizing low work function metal electrodes. However, inverted solar cells with a V2O5 hole extraction layer could not be obtained due to possible incompatibility of the V2O5 coating process with the underlying absorber layer. In the case of MoO3 interlayers, the introduction of additional layers led to working inverted solar cells.

A generic approach to design optoelectronic devices using renewable biopolymers is demonstrated. As a proof of principle, a biopolymer/CuInS2 nanocomponent-based solar cell has been assembled by using a cellulose derivative with a reasonable life cycle performance, namely trimethylsilyl cellulose (TMSC). The solar cells are manufactured using a mixture of copper and indium xanthates as precursors, which decompose and form CIS nanoparticles within the biopolymer matrix during a thermal treatment, which was investigated by in situ combined grazing incidence small and wide angle X-ray scattering experiments. The growth of the nanoparticles is thereby controlled by the TMSC matrix. The nanocrystals exhibit an average diameter of approx. 4 nm. Using this composite, it was possible to fabricate solar cells, generating current in a wide range of the solar spectrum and exhibiting power conversion efficiencies of ca. 1%., This is a open access preprint of https://doi.org/10.1021/acssuschemeng.6b02871

A generic approach to design optoelectronic devices using renewable biopolymers is demonstrated. As a proof of principle, a biopolymer/CuInS2 nanocomponent-based solar cell has been assembled by using a cellulose derivative with a reasonable life cycle performance, namely trimethylsilyl cellulose (TMSC). The solar cells are manufactured using a mixture of copper and indium xanthates as precursors, which decompose and form CIS nanoparticles within the biopolymer matrix during a thermal treatment, which was investigated by in situ combined grazing incidence small and wide angle X-ray scattering experiments. The growth of the nanoparticles is thereby controlled by the TMSC matrix. The nanocrystals exhibit an average diameter of approx. 4 nm. Using this composite, it was possible to fabricate solar cells, generating current in a wide range of the solar spectrum and exhibiting power conversion efficiencies of ca. 1%.